JP3125670B2 - Transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device, and more particularly to a transfer device suitable for transferring a magnetic work such as a lead frame.

[0002]

2. Description of the Related Art Conventionally, when a hoop material such as a lead frame is transported in a manufacturing process, the hoop material is not cut into a fixed length.
It is customary to convey it in a continuous state. The conventional conveying device has a feed claw that reciprocates. When feeding the hoop material, the feed claw is moved by hooking the hole in the hoop material, and when the feed claw returns, the feed claw is disengaged from the hole in the hoop material. The wood is kept stationary. At this time, in order to prevent the hoop material from moving backward, the hoop material is pressed by using an air cylinder or a one-way clutch. It is necessary to suppress bending and vibration in order to obtain the stop position accuracy of the hoop material, and the hoop material is always provided with tension by combining a brake sprocket and a tension roller.

[0003]

However, in the conventional conveying device, as the distance from the hoop material feeding reference (feeding claw) increases, the stop position due to the accumulation of the pitch accuracy of the hoop material and the extension of the hoop material due to heat. There is a disadvantage that the accuracy is easily adversely affected. Also, due to the reciprocating movement of the feed claw by the cam, the return operation time affects the tact time,
In addition, there is a disadvantage that the higher the speed is, the more the vibration and the noise become. Further, a device for preventing the hoop material from moving backward and a device for applying tension are required, and there is a drawback that the device becomes large.

As described in Japanese Utility Model Publication No. 7-35388, a lead frame is guided along the upper surface of a non-magnetic guide rail, and a non-magnetic guide member is provided on one side edge of the upper surface of the guide rail. There has been proposed a transfer guide device in which magnets are buried at appropriate intervals inside the guide member. In this case, the side edge of the lead frame is attracted by magnetic force and comes into contact with the guide member, so that the position accuracy is excellent, and a device for preventing the hoop material from going backward or a device for applying tension. There is an advantage that it becomes unnecessary.

However, also in this case, it is necessary to use a transfer means such as a feed claw to transfer the lead frame, and it is difficult to perform high-speed transfer with low vibration and low noise. Also, since the lead frame is in close contact with the guide member, frictional resistance acts between the lead frame and the guide member, and when the transfer means engages with the lead frame and transfers the lead frame, a large load is partially applied to the lead frame. Therefore, there is a fear that the lead frame may be elongated or deformed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a transfer device which can transfer a magnetic work at high speed with low vibration and low noise, and can perform high-precision positioning. Another object of the present invention is to provide a transfer device that can transfer a work without imposing an excessive load on the work.

[0007]

To achieve the above object, according to an aspect of the present invention is an apparatus for conveying a magnetic workpiece having two surfaces adjacent to guide slidably the first surface of the workpiece and non-magnetic rail having a guide surface, having a conveying surface in contact with the second surface of the <br/> work, and belt movable nonmagnetic along said rails, thereby driving to rotate the belt drive Means, and a belt facing the rail, and the second surface of the work is transported by the belt.
A magnet for generating a magnetic force to come into close contact with the Okumen, further comprising a
A transport device characterized by the following.

[0008] The magnetic force of the magnet is as follows.
And the second component of the workpiece
It is desirable to have a component force to bring one surface into contact with the rail.
No. It is preferable that a yoke is attached to both poles of the magnet and the guide surface of the rail is located near a boundary between one pole of the magnet and the yoke. Sa
Further , the present invention is suitable for conveying a thin long work such as a magnetic lead frame . This place
In this case, the first surface of the work
The second side of the work is the side of the lead frame.
It may be the bottom of Ivar.

When the belt is moved along the rail by the driving means, the work moves integrally with the belt because the second surface of the work is in close contact with the conveying surface of the belt by the magnet. At this time, since the first surface of the work is slidably guided by the guide surface of the rail, the work is transported while maintaining a stable posture. During transport, the workpiece
Since it moves while being in close contact with the belt , the load does not concentrate on a part of the work. Therefore, the work can be conveyed without imposing an excessive load on the work, and deformation and bending of the work can be prevented.

If the belt is stopped suddenly, the work may be displaced by inertia force. However, if the second surface of the work is brought into close contact with the belt by magnetic force ,
Even if the work is suddenly stopped, it is possible to stop the work without causing a positional shift. Further, a device for preventing the hoop material from moving backward or a device for providing tension is not required, and the device is reduced in size. Base of the present invention
Since the belt is driven to rotate and does not require a return operation, high-speed conveyance is possible, and vibration and noise do not become intense even when the speed is increased.

The belt conveying surface in the present invention does not need to be a smooth surface, but may have irregularities. Further, the belt is desirably formed of a material having a thin shape and a high magnetic permeability so that the magnetic force of the magnet penetrates the belt and acts on the work efficiently. The two adjacent surfaces of the workpiece need not be perpendicular to each other, and one of them may be a curved surface. The magnetic force of the magnet is
It is desirable to have a component force for bringing the surface into close contact with the carrier and a component force for bringing the first surface of the work into contact with the rail, but in order to minimize the sliding friction between the work and the rail, the second surface of the work should be The component force that comes into close contact with the carrier is the first of the workpiece.
It is desirable to determine the position of the magnet so that it is greater than the component force that causes the surface to contact the rail.

[0012]

1 to 7 show a first embodiment of the present invention, in which a transfer apparatus uses a lead frame W as a work.
Used to transport The lead frame W of this embodiment is cut into a fixed length as shown in FIGS. The lead frame W is formed by punching a thin magnetic metal plate. A tie bar b having a feed hole a is formed on one side edge in the longitudinal direction, and the tie bar b protrudes from the tie bar b in a substantially orthogonal direction on the other side edge. A plurality of terminals c
Are integrally formed.

The present transport device includes a rail 1 that slidably supports the side surface (first surface) of the tie bar b of the lead frame W. The rail 1 is made of a non-magnetic material such as stainless steel, aluminum, resin or the like, and its upper surface (guide surface) 2
In order to reduce the frictional resistance with the lead frame W,
A fluororesin coating or the like is appropriately applied. The rail 1 is fixed to the front surface of a rail base 3 made of a non-magnetic material by screws 4 as shown in FIG. On the rail base 3, permanent magnets 5 having yokes 6 and 7 made of a magnetic material attached to both N and S poles are arranged, and fixed to the rail base 3 by non-magnetic magnet holders 8 provided at appropriate intervals. I have. Although the yokes 6 and 7 are long members having substantially the same length as the rail base 3, the permanent magnets 5 need not be long magnets like the yokes 6 and 7, and may be arranged intermittently. Note that the magnet holder 8 is fixed to the rail base 3 by screws 9.

Both ends of the rail base 3 are horizontally supported by support bases 10, 11 as shown in FIGS. A drive motor 12 composed of a servomotor, a pulse motor, or the like is fixed to one support base 10. The rotating shaft 13 of the motor 12 is connected to a driving pulley 15 via a coupling 14. The other support 1
1 is a slide table 1 that can slide horizontally.
A tension pulley 18 serving also as a driven pulley is rotatably attached to the slide table 16 via a support shaft 17. A tension adjusting bolt 20 is screwed into a bracket 19 fixed to the upper portion of the support base 11, and a tension spring 21 is disposed between the bolt 20 and the slide table 16. Therefore, the tension pulley 18 is urged in a direction opposite to the driving pulley 15 by the spring force of the tension spring 21, and the spring force can be adjusted by the bolt 20. Thereby, the tension of the belt 22 described later can be adjusted.

A belt 22 made of a non-magnetic material is wound around the driving pulley 15 and the tension pulley 18 with tension, and is driven to rotate in the horizontal direction. The belt 22 may be a resin belt or a metal belt such as stainless steel. Belt 22
Is formed to be thin, and the conveying surface (feed side) 22 of the belt 22 is
a is horizontally movable in a gap between the upper yoke 6 and the rail 1. The back surface of the belt 22 is supported by the side surface of the yoke 6, and the transport surface 22 a of the belt 22 is substantially perpendicular to the guide surface 2 of the rail 1. The transfer surface 2
2a is the end surface (second surface) of the tie bar b of the lead frame W
Will adhere.

Here, the operation of the present transport device will be described. Since the yokes 6 and 7 are arranged on the upper and lower poles of the permanent magnet 5, magnetic lines of force gather between the boundaries between the yokes 6 and 7 and the permanent magnet 5, as shown in FIG. Since the guide surface 2 of the rail 1 is located near the boundary between the upper yoke 6 and the permanent magnet 5, the tie bar b of the lead frame W that slides on the guide surface 2 is also arranged at the site where the magnetic lines of force gather. It will be effectively affected by magnetic force.

At this time, the attraction force by the magnetic force to the lead frame W can be divided into two components, X and Y. That is, the component force X is the tie bar b of the lead frame W.
The component force Y is a component force for bringing the side surface of the tie bar b of the lead frame W into close contact with the rail 1. The component force X is larger than the component force Y.

Due to the magnetic force of the permanent magnet 5 as described above, the end surface of the lead frame W is
While maintaining close contact with the guide surface, the side surface is kept in contact with the guide surface 2 of the rail 1. Here, when the belt 22 is driven, the lead frame W is conveyed integrally with the belt 22 while sliding on the rail 1. Therefore, even when the belt 22 is moved at a high speed, the lead frame W can be prevented from rising, bending, deforming, and the like. In addition, since the belt 22, which is a conveyor, is driven to rotate, it is possible to suppress the generation of vibration and noise as in a conventional reciprocating feed claw.

Since the belt 22 and the lead frame W are in close contact with each other over the entire length, a contact state can be secured over a long distance, and there is no possibility that a large load acts locally on the lead frame W. Therefore, even if the lead frame W is formed of a thin material, deformation of the lead frame W,
Warpage, bending, and the like can be effectively prevented.

When the belt 22 is stopped, the lead frame W maintains the stop position by the magnetic force of the permanent magnet 5, so that even if vibration or impact is applied in this state, the position of the lead frame W is not disturbed. High positioning accuracy can be obtained. Therefore, when the present transport device is used in an electronic component assembling process or a characteristic measuring process, the position of the electronic component is less likely to be misaligned. Further, since a device for preventing the backward movement of the lead frame W and for providing tension is not required, the device can be reduced in size and simplified.

Conventionally, it is difficult to transport the hoop material by cutting it into a fixed length, and the hoop material is transported in a continuous state. However, in the present invention, since the hoop material is transported in close contact with the belt 22,
The hoop material can be cut to a certain length and transported. Therefore, the present transfer device can be applied to products with many specifications.

The belt 22 can change the feed speed of the lead frame W by controlling the driving of the motor 9, and can perform continuous feed, tact feed, and forward / reverse switching in addition to continuous feed. .

In the above embodiment, a single unit has been described, but a plurality of units can be connected in series as shown in FIG. In this case, the transport path becomes long, and the workpiece can be transported between many steps. In this case, by controlling the motor of each unit, the belt of each unit can be operated synchronously. In this way, adding units according to equipment specifications,
It is easy to delete, and the degree of freedom in design is increased.

FIG. 9 shows another example of a work that can be carried by the carrying device of the above embodiment. The work W is, for example, a pallet made of a magnetic material, and has a plurality of recesses d formed on the upper surface thereof, and small parts e such as chip components can be stored in these recesses d. Also in this case, the pallet W
May be slidably supported by the guide surface 2 of the rail 1, and the side surface of the pallet W may be brought into close contact with the belt 22. Note that the inner wall of the concave portion d may be formed of an elastic body such as silicon rubber so that the chip component e is not damaged by the inner wall of the concave portion d.

FIG. 10 shows a second embodiment of the transport device according to the present invention. This transfer device uses a non-magnetic turntable 30 having a cylindrical peripheral wall 31 as a transfer body. The rotation shaft 32 of the turntable 30 is a motor 33
Driven by Permanent magnet 3 on the inner peripheral side of peripheral wall 31
4 and yokes 35 and 36 are arranged on both upper and lower poles thereof,
An annular or arcuate rail 37 is arranged on the outer peripheral side. The work W is slidably disposed on the rail 37, and its side surface is in close contact with the peripheral wall 31 of the turntable 30 by the magnetic force of the permanent magnet 34. Therefore, when the turntable 30 is rotated, the work W is conveyed in the circumferential direction integrally with the peripheral wall 31 of the turntable 30. In the case of this embodiment, as in the case of the first embodiment, the turntable 3
Even when 0 is rotated at a high speed, vibration and noise can be reduced and high stop position accuracy can be obtained in the traveling direction of the workpiece W.

FIG. 11 shows a third embodiment of the transport device according to the present invention. This transport device transports a wide work W such as an IC lead frame having tie bars f on both left and right sides. Two non-magnetic rails 41 and 42 are fixed on a base 40 in parallel. A belt 22 similar to that shown in FIG. Belt 2
A magnet (not shown) and a yoke 6 are arranged on the inner side of the belt 2 in parallel with the moving direction of the belt 22. A driving pulley 15 is disposed at one end of the belt 22.
5 is driven by the motor 12 arranged below the base 40. A tension pulley 18 also serving as a driven pulley is rotatably supported on a base 40 at the other end of the belt 22. In this embodiment, a pair of rails 4
Since the lower surfaces of both sides of the work W are supported by the work 42, the work W can be stably conveyed even if the work W is a wide member.

The above embodiments are merely examples of the present invention, and it goes without saying that various modifications are possible. In the above embodiment, the guide surface that slidably guides the first surface of the work is a horizontal surface, and the transfer surface that contacts the second surface of the work is the vertical surface, but the transfer surface is a horizontal surface,
The guide surface may be a vertical surface. Further, the guide surface and the transport surface need not be perpendicular to each other, but may be inclined. In the above embodiment, the yokes are attached to both poles of the permanent magnet. However, the work can be attracted to the guide surface and the transfer surface without using a yoke. However, when the yoke is used, the magnetic force density increases, and the work can be more effectively attracted. The magnet in the present invention is not limited to a permanent magnet, and an electromagnet can be used.
In particular, if the electromagnet is demagnetized when the work is taken out of the transfer device, the work can be easily taken out.

[0028]

As apparent from the above description, according to the present invention, the first surface of the work is slidably guided by the non-magnetic rail, and the second surface of the work is non-magnetic belted by the magnetic force. />, So that it can be positioned with high accuracy even when it is transported at high speed. In addition, the posture of the work is stabilized , and the work can be stopped without causing a positional shift even when the work is suddenly stopped. Further, since the belt is driven to rotate, a return operation such as a feed claw is not required, and the workpiece can be conveyed at high speed with low vibration and low noise. Further, a work backward prevention device and a tension applying device are not required, and the transfer device can be reduced in size and simplified.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an example of a transport device according to the present invention.

FIG. 2 is a front view of a specific example of the transport device shown in FIG.

FIG. 3 is a plan view of the transfer device of FIG. 2;

FIG. 4 is a left side view of the transfer device of FIG. 2;

FIG. 5 is a right side view of the transfer device of FIG. 2;

FIG. 6 is an enlarged perspective view of a portion of the transfer device of FIG. 2 taken along line AA.

FIG. 7 is a sectional view showing a direction of a magnetic force of the transfer device of FIG. 2;

FIG. 8 is a schematic perspective view of a state in which a plurality of the transfer devices of FIG. 1 are connected.

FIG. 9 is a perspective view of another example of the work.

FIG. 10 is a sectional view of a transport device according to a second embodiment of the present invention.

FIG. 11 is a perspective view of a transport device according to a third embodiment of the present invention.

[Explanation of symbols]

 W Work 1 Rail 2 Guide surface 5 Permanent magnet 6,7 Yoke 12 Motor 15 Drive pulley 18 Tension pulley (Driving pulley) 22 Belt (Conveyor) 22a Transport surface

Continuation of front page (56) References JP-A-4-329011 (JP, A) JP-A-4-208540 (JP, A) JP-A-4-36232 (JP, U) (58) Fields surveyed (Int .Cl. ⁷ , DB name) H01L 21/50

Claims (4)

(57) [Claims] An apparatus for transporting a 1. A magnetic workpiece having two surfaces adjacent and non-magnetic rail having a guide surface for guiding slidably the first surface of the workpiece, the second of said workpiece has a conveying surface in contact with the surface, the belt movable nonmagnetic along said rail <br/> Le, driving means for driving to rotate the belt, a position opposed to the rail in between the belt And a magnet that generates a magnetic force for bringing the second surface of the work into close contact with the transfer surface of the belt . 2. The transfer device according to claim 1, wherein the magnetic force of the magnet causes the second surface of the work to come into close contact with the belt.
And the component force that brings the first surface of the workpiece into contact with the rail.
A transport device comprising: 3. The transfer device according to claim 1 , wherein a yoke is attached to both poles of the magnet, and the guide surface of the rail is located near a boundary between one pole of the magnet and the yoke. A transfer device characterized by the above-mentioned. 4. The transfer device according to claim 1, wherein the work is a magnetic lead frame, and the first surface of the work is a side surface of a tie bar of the lead frame.
And the second surface of the work is the bottom surface of the tie bar of the lead frame.
Conveying apparatus, characterized in that it.